RevitalizationofRivers In IndiaDraftPolicy Recommendation stream network, slope/contour, forest legal boundaries, settlement locations and village boundaries. The main criterion that will be used to differentiate the various land uses in the study area in these type groups is their similarity, such as in the height and extent of forest canopy in the case of vegetative covers, and the predominance of a paved, impervious surface devoid of vegetation in the case of commercial and rural residential zones. The percentage of land use within the proposed area will be calculated and grouped in each basin which can be determined from the prepared data set (Map layers). Finally, field validation will be conducted with processed data base. 3.2. Geology – To understand the geology of the area including rock formations and types of rock, structural aspects will be studied through field examinations. 3.3. Soil Study – Physical and chemical characteristics, types of soil, and depth profile data will be collected from the existing source for further understanding and analysis. 3.4. Rainfall – Rainfall data will be collected from the existing data source for the proposed region to understand the rain pattern. 3.5. Streamflow – Flow rate data will be collected for the past few decades to understand the existing scenario. 3.6. Evapotranspiration (ET) – If the ET data is not available then it will be calculated from collected rainfall and streamflow, etc. The mass-balance approach of Giusti (1978) will be used to estimate evapotranspiration (ET) within the study area. In this approach, ET can be considered to be the difference between rainfall and runoff (ET = P–RO) where P is the basin average precipitation and RO is runoff. According to Giusti (1978), ET increases until a threshold in rainfall is reached, beyond which it progressively decreases with further increases in rainfall. The rainfall and streamflow data will be used to estimate evapotranspiration. 3.7. Groundwater – Available groundwater data will be used to understand the current condition of the basin. Annexures 291

RevitalizationofRivers In IndiaDraftPolicy Recommendation 4. EFFECTS OF FOREST COVER ON BASE FLOW OF STREAMS – TO DETERMINE ONCE FOREST IS DEVELOPED 4.1. Land use analysis – To determine the changes in land cover and land use pattern. 4.2. Rainfall and Climate - Rainfall stations equipped with tipping-bucket-type rainfall gauges were installed as part of this study at different altitudes to account for the spatial variation in rainfall within the basins. Additional climatological data will be measured to calculate and analyse the rainfall patterns of the region. In addition, installed weather station data will be used to determine temperature changes, wind direction, air moisture, etc. 4.3. Hydrology - Test holes will be drilled and a series of piezometers can be installed as much as needed in the proposed basins to obtain the lithologic and groundwater data which define the hydrogeology of the study area. Water-level measurements will be made at regular intervals, and also a slug test can be conducted at representative piezometers (test well) to estimate hydraulic conductivity. The Bouwer and Rice (1976) analysed method may be adopted to compute the values from the slug-test data. Groundwater levels at selected piezometers in test bore wells will provide storage and pathways for groundwater movement. 4.4. Streamflow - Streamflow gauging stations will be installed through the length of the stream stretch in the proposed basins to collect continuous streamflow data. Result of the steep slope of the stream channels and the steep hydraulic gradient at the younger stage of stream runoff may occur rapidly. So, relatively streamflow discharge measurements will be measured and analysed to investigate the characterization of the occurrence of low flows in the particular stream. Continuous daily streamflow data will be also estimated for the larger basins and continuous streamflow data for the tributaries. ● Total streamflow was separated into base-flow and runoff components. The base-flow component of continuous streamflow estimated at proposed basins obtained with Hydrograph Analysis Tool. ● The base-flow component will be computed using the “One- 292 Annexures